In a conventional electronic device, operating as a USB host, the processor is able to write data into a system memory. A host controller integrated circuit is then able to read the data directly from the system memory. In order to be able to do this, the host controller needs to master the system memory. However, since the system memory is shared between the host controller integrated circuit and the system processor, this requirement that the host controller be able to master the system memory requires the use of a bus master, which is specific to the system processor. Moreover, while the host controller is mastering the system memory, the core function of the device, running under the control of the system processor, may be disrupted.